Previous systems for extracting liquid from dilute slurries, such as waste activated sewage sludge, include systems of the type described in U.S. Pat. No. 3,796,317 to Lippert et al. In this prior art dewatering system, a pair of concentrically mounted endless belts, one belt formed of a screen-like material and the other porous capillary belt, are employed as part of a system which combines the action of capillary force with mechanical compression to extract the desired amount of liquid.
By the present invention, there is provided a dewatering system which has improved features over systems such as that described in U.S. Pat. No. 3,796,317. The particular features of the present invention include a spring-loaded or balanced sludge feed tray incorporating an adjustable flow splitter plug, along with spring-loaded sludge side guides. A sludge cake compression section design allowing two-position adjustment of the compression roller is employed as a component in the backflushing of the sludge carrier screen using cake effluent. Also, a particular solids loading is employed which results in a significant improvement in performance of the dewatering system.